#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;
#define rep(i, a, b) for (int i = (a); i <= (b); i++)
#define per(i, a, b) for (int i = (a); i >= (b); i--)
#define endl '\n'
const int N = 1e6 + 5;

int n, m;
pii a[N];

int main() {
  ios::sync_with_stdio(0), cin.tie(0), cout.tie(0);
  cin >> n;
  rep(i, 1, n) cin >> a[i].first >> a[i].second;
  sort(a + 1, a + n + 1);
  int cnt = 1;
  int r = a[1].second;
  rep(i, 1, n) {
    if (a[i].first >= r) {
      cnt++;
      r = a[i].second;
    } else {
      r = min(r, a[i].second);
    }
  }
  cout << cnt;
  return 0;
}